I took the "new to me" Cooper M21 in .204 to the range today and did some testing. Here's a photo of one of the targets....this string was loaded with 26.6gr of H335. I jerked the flyer off to the left, and the 4 shot hole measured .203. I'm not finished load work, and will do some testing with other powders and bullets as well. The 39gr SBKs are near and dear to my heart.....if a rifle, with decent hand loads, won't shoot the 39's......it must be the rifle....or the shooter.
The person I bought it from had it re-barreled by Cooper a few years ago, and Rob Behr told him that they'd used a "minimum spec" reamer as opposed to one of their "stock" reamers. So far I've only been able to chamber unfired brass in it and I'll have to keep the reloads separate from those I use in my Ruger VT and Rem700 LVSF.......not a problem, since it looks like it'll be a real shooter.
